A fourth Pfizer/BioNTech COVID-19 vaccine shot provides short-lived protection against the infection of the virus, and can't afford the predicted protection against severe illness, a new study showed.
Published on Tuesday in the New England Journal of Medicine, the study examined the health records of more than 1.25 million persons who were vaccinated with the fourth Coronavirus vaccine between January and March who are over 60. Those two months marked the climax of the Omicron variant.
After examining the data, the experts identified that the levels of COVID-19 infections in the fourth week after the fourth dose were lower than in people who received only three doses by a factor of 3.5.
Furthermore, the protection against the severe illness didn't seem to be effective six weeks after the fourth shot.
The currently available COVID-19 vaccines are effective in protecting against the original strain of the virus. But, not all of them are protective against Omicron is significantly different.
Last month, US health authorities approved a second COVID-19 booster dose for two vaccines: Pfizer and Moderna, for people aged 50 and older.
The essential motive for issuing such a decision was raising the immune response of aged people against the Omicron variant risks.
The U.S. Food and Drug Administration agency said the fourth dose will be dedicated to those who were vaccinated by the Pfizer Inc (PFE.N)/BioNTech and Moderna vaccines are to be administered at least four months after the latest dose.
The FDA also authorized the fourth shot for younger people who aged 12 and older for the Pfizer/BioNTech shot and 18 and older for Moderna’s.
Last year, the US Centers for Disease Control and Prevention officially approved booster COVID-19 vaccine doses for people who are in high risk.
The CDC board of experts recommended giving those extra shots to older people aged over 65 years old, nursing houses people, and persons who suffer from a severe disease that could be developed by the coronavirus.
However, the board rejected offering any booster shots to workers of medical professions, and health care workers.